I have a gross (less now) of G-E PH/11B bulbs. I know (think) the GN on blue bulbs is about two stops less than on clear bulbs. However my question is what does the "PH" mean or stand for ? A black cool cat guy I met on 14th street outside the Plumm using a 4x5 Graflex said it meant "purple haze". I really didn't believe him.

Curious,
George

FWIW: I shot PH/11B bulbs tonight at different distances, 5, 10, and 16 feet. The Lucky 100 B&W negs look right on target exposure wise. But their still wet so I won't know for sure until tomorrow when I put them on the light box.

Here in the United States we can still purchase new incandescent light bulbs with the GE brand name on them. Presumably GE manufactures them.
Your theory of the "PH" standing for "PHotography" has a high probability of being correct. Even more probable is that it stands for the "PHotographic" variation to your theory!

Cool Cat "Lewis" was right... PH stands for Purple Haze. The Lucky 100 negs were a little heavy. After shooting two more Lucky 100 B&W 120 rolls using the 23 Graphic back I came to the conclusion the light colored 11B blue bulbs are one stop slower (GN-220) than the clear types (GN-320) of the same number. I haven't tried the darker colored blue bulbs as I have no interest in them and they're sleeveless anyway.

BTW: I got an anonymous email message stating that I'm an "AH" for wasting photoflash bulbs on taking pictures. Gee, that got me thinking, maybe I should get modern and use a stroboscopic speed light.

My Photo Lab Index is Pre-war so it doesn't have much about color flash (hence no 11B) but the No. 11 was variously called a "synchro-flash" and a "PHotoflash No.11" so I suspect the PH was for Photoflash.

And I wonder what Mr. Anonymous emailer suggest you do with flash bulbs? build a shrine? sell them on ebay to somebody else who will build a shrine? I say you keep the dead soldiers and put them on ebay on April 1st and say these were pre-tested, and only used once. You can also cross category them into the astronomy section calling them an early and rare reverse painting on glass map of the moon as a spent bulb does look like the moon._________________"In order to invent, you need a good imagination and a lot of junk" Thomas Edison

For what its worth my copy of the Photo Lab Index (updated through supplement #171, early 1980s) lists the PH/11 flashbulb but not the PH/11B.
Comparing other number flashbulbs that list both a clear and a blue bulb seems to show a loss of 2/3 to 1 1/2 stops of output for the blue bulb.
As for the email from "Mr. Anonymous" just remember that those who send such emails are describing themselves, not the person receiving their garbage!!